Global Warming


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This is a PowerPoint presentation I did for a Climate & Weather class in my MAter's program in Science Education.

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Global Warming

  1. 1. Global Warming Stephanie Fendrick
  2. 2. What is Global Warming? <ul><li>Global warming is defined as an increase in the average temperature of Earth’s surface. </li></ul>
  3. 3. How Warm is it Getting? <ul><li>Between 1880 and 2000, global annual average temperatures rose about 1.2°F. </li></ul><ul><li>Between 2000 and 2100, scientists estimate that global annual average temperatures will rise anywhere between about 3.5°F and 8°F. </li></ul><ul><li>That rate of increase would be much larger than most rates of past increases. </li></ul><ul><li>Of the 20 hottest years on record, 19 occurred in the 1980’s or later. </li></ul>
  4. 4. Causes of Global Warming <ul><li>A majority of climatologists have concluded that human activities are responsible for most of the warming. </li></ul><ul><li>The main human activities that contribute to global warming are the burning of fossil fuels (coal, oil, and natural gas) and the clearing of land. </li></ul><ul><li>Most of the burning occurs in automobiles, in factories, and in electric power plants. </li></ul>
  5. 5. Causes of Global Warming <ul><li>The burning of fossil fuels creates carbon dioxide, a greenhouse gas that slows the escape of heat into space. </li></ul><ul><li>The clearing of land contributes to the buildup of CO 2 by reducing the rate at which the gas is removed from the atmosphere or by decomposition of dead vegetation. </li></ul>
  6. 6. Causes of Global Warming <ul><li>Since the beginning of the Industrial Revolution: </li></ul><ul><li>Atmospheric concentrations of carbon dioxide have increased nearly 30% </li></ul><ul><li>Methane concentrations have more than doubled </li></ul><ul><li>Nitrous oxide concentrations have risen by about 15%. </li></ul>
  7. 7. Who’s to Blame? <ul><li>The U.S. is the world’s #1 global warming polluter and #2 per capita, with 23% of the world’s global warming pollution yet only 4% of the world’s people. </li></ul><ul><li>The U.S. uses twice as much energy as Europe to achieve roughly the same standard of living. </li></ul><ul><li>In 1997, 1998 and 1999 China, which emits half the amount of pollution as the U.S., cut its coal burning, decreasing its carbon emissions, at the same time that U.S. emissions continued to increase. </li></ul>
  8. 8. Effects of Global Warming: Higher Sea Levels <ul><li>Warmer global temperatures lead to more melting of the polar ice caps and other surface ice. </li></ul><ul><li>Greenland ice is melting twice as fast as it was in 1996. </li></ul><ul><li>This melting leads to higher sea levels, which could swallow up large coastal areas. </li></ul>
  9. 9. Effects of Global Warming: Higher Sea Levels <ul><li>The loss of the planet’s ice cover also alters its relationship with the sun. </li></ul><ul><li>Polar ice has a high albedo, ocean water has a low albedo. </li></ul><ul><li>As more polar ice melts into the ocean, less heat is reflected by the planet, and more is absorbed by the ocean. </li></ul>
  10. 10. Effects of Global Warming: Even More CO 2 <ul><li>Permafrost is land that has been continuously frozen for a long period of time. It has been melting at an unprecedented rate. </li></ul><ul><li>As the permafrost melts, it releases partially decayed organic matter, also releasing gases that will turn into methane and CO 2 . </li></ul><ul><li>It is estimated that 200-800 gigatons of carbon exist buried in permafrost. By comparison, human carbon output is 7 gigatons per year. </li></ul>
  11. 11. Effects of Global Warming: Even More CO 2 <ul><li>All glaciers in the park will be gone by 2070 if retreat continues at its current rate. </li></ul><ul><li>The photo is a comparison of the size of Grinnell Glacier. The top image was taken in 1911; bottom image was taken in 2000. </li></ul>Glacier National Park, Montana
  12. 12. Effects of Global Warming: Endangered Marine Life <ul><li>Water that is warmer than normal by only 2° to 3 �° F has been linked to coral bleaching. When corals bleach, they expel the algae that give them their color and nourishment. The corals turn white and, unless the water temperature cools, they die. </li></ul><ul><li>Warmer water also leads to the spread of diseases that affect sea life. </li></ul><ul><li>Polar bears are drowning as warmer waters widen the distance from ice floe to ice floe. </li></ul>
  13. 13. Effects of Global Warming: Changes of Habitat <ul><li>Plants and animals generally react to consistently warmer temperatures by moving to higher latitudes and elevations, taking them out of their natural habitat. </li></ul><ul><li>Recent studies reveal that some species have already started to shift their ranges, consistent with warming trends. </li></ul>
  14. 14. Effects of Global Warming: Drought <ul><li>Global warming also leads to drought conditions in dry regions. </li></ul><ul><li>Higher temperatures bake moisture out of the soil faster. </li></ul><ul><li>The percentage of Earth’s surface suffering drought has more than doubled since the 1970’s. </li></ul>
  15. 15. Effects of Global Warming: Drought <ul><li>Melbourne, Florida endured 24 days above 95° � F; nighttime temperatures in Tampa remained above 80 �° F for 12 days. </li></ul><ul><li>The photo is a dry lake during drought in Orlando. </li></ul>
  16. 16. Effects of Global Warming: Drought <ul><li>In dry mountainous regions, water comes from the snowpack that collects on peaks all winter and slowly melts off in warm months. </li></ul><ul><li>Early arrival of spring and hot summers cause the snowpack to melt too early, so by the time it’s needed, it’s gone. </li></ul><ul><li>Snowpack levels in CA, WA and OR are a fraction of what they were in the 1940’s. </li></ul>
  17. 17. Effects of Global Warming: Extreme Weather <ul><li>Extreme weather conditions might become more frequent and therefore more damaging. </li></ul><ul><li>Changes in rainfall patterns could increase both flooding and drought in some areas. </li></ul><ul><li>More hurricanes and other tropical storms might occur, and they could become more powerful. Warmer water is like rocket fuel for typhoons and hurricanes. </li></ul>
  18. 18. Effects of Global Warming: Extreme Weather <ul><li>Two studies last year found that in the past 35 years the number of Category 4 and 5 hurricanes worldwide has doubled. </li></ul><ul><li>Also, the wind speed and duration of all hurricanes has increased 50%. </li></ul><ul><li>Warmer temperatures means tropical storms could start turning up in non-tropical places. </li></ul>
  19. 19. Effects of Global Warming: Human Health <ul><li>Tropical diseases, such as malaria and dengue, might spread to larger regions. </li></ul><ul><li>Longer-lasting and more intense heat waves could cause more deaths and illnesses. </li></ul><ul><li>Floods and droughts could increase hunger and malnutrition. </li></ul>
  20. 20. What Can We Do? <ul><li>Limit CO 2 emissions. Two effective techniques for limiting CO 2 emissions would be (1) to replace fossil fuels with energy sources that do not emit CO 2 , and (2) to use fossil fuels more efficiently. </li></ul>
  21. 21. Alternative Energy Sources <ul><li>Alternative energy sources that do not emit CO 2 include the wind, sunlight, nuclear energy, and underground steam. </li></ul><ul><li>Devices known as wind turbines can convert wind energy to electric energy. </li></ul><ul><li>Solar cells can convert sunlight to electric energy, and various devices can convert solar energy to useful heat. </li></ul><ul><li>Geothermal power plants convert energy in underground steam to electric energy. </li></ul>
  22. 22. The Kyoto Accord <ul><li>Delegates from more than 160 countries met in Kyoto, Japan, in 1997 to draft the agreement that became known as the Kyoto Protocol. That agreement calls for decreases in the emissions of greenhouse gases. </li></ul><ul><li>The protocol would take effect as a treaty if (1) at least 55 countries ratified it, and (2) the industrialized countries ratifying the protocol had CO2 emissions in 1990 that equaled at least 55 percent of the emissions of all 38 industrialized countries in 1990. </li></ul><ul><li>By early 2003, more than 100 countries, including nearly all the countries classified as industrialized under the protocol, had ratified the agreement. The U.S., under President Bush, has refused to ratify the Kyoto Accord. </li></ul>
  23. 23. Bibliography <ul><li> </li></ul><ul><li> </li></ul><ul><li>Kluger, Jeffrey, “The Tipping Point.” Time 3 April 2006: 28-42. </li></ul><ul><li>World Book Multimedia Encyclopedia. CD-ROM. World Book, Inc.: 2004. </li></ul>